Sorry, I didn't have time to elaborate earlier.
Around 2004, CAT approached Morris Kessler of ATI to manufacture an amplifier for them that wouldn't break- the request was: "build the amp you've always wanted to build, but couldn't because your OEM customers had cost restrictions" . What this resulted in was a line of amplifiers (and a sister company) called Monaco Audio; these amps are (as far as I know) still on display at Creative Home Theater in Las Vegas.
Fast forward to 2006, and Monaco has now morphed into CAT amplifiers with a different aesthetic (Neal Feay) and more models- at this time there is no official partnership with Theta (though Theta processors are used in CAT systems- they are not spec'ed by CAT). CEDIA 2007 there is talk about ATI purchasing Theta, by the following CES ATI owns Theta and that's when CAT product was used to demo Theta gear.
I'm proud to say I was integral in that first suite at CES that contained CAT and Theta gear- both the multi-channel system and the 2 channel system. (I was general manager at CAT at that time)
Now, CAT specs Theta processing in their highest level systems- usually with multiple GenVIII DACs, and several CAT DSPs, followed by a plethora of CAT amplification (powered by SAE..says so right on the front).
There's your brief history, Bulldogger.